Image pickup apparatus and image pickup system

ABSTRACT

A camera apparatus and a camera system of the present invention are configured so that a lens unit is attachable/detachable. The lens unit contains at least a lens and an iris, and contains a memory storing setting information required for operating the lens and the iris. When a camera microcomputer checks detection information stored in a memory in a sub-microcomputer at a time of start-up of the camera apparatus, and first detection information is stored in the memory, the setting information is acquired from the lens unit. When second detection information is stored in the memory, the setting information is acquired from another memory in the camera apparatus. Due to this configuration, the time for shifting the switch-on to a photographable state is shortened, and the ease of convenience can be enhanced.

This application is a continuation of U.S. application Ser. No.11/556,781, filed Nov. 6, 2006, which application is incorporated hereinby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a camera apparatus to which a lens unitis attachable/detachable. The present invention also relates to a camerasystem having a camera unit and a lens unit exchangeable with respect tothe camera unit. In particular, the present invention relates to asystem in which a camera unit and a lens unit can communicate with eachother so that unique information of the lens unit can be communicated tothe camera unit.

2. Description of Related Art

Recently, in a camera system of an exchangeable lens system, respectivedriving systems such as focus driving means, exposure driving means, andzoom driving means are provided on a lens unit side, and control meansfor controlling the respective driving systems on the lens unit side isprovided on a camera unit side. Furthermore, the camera system includescommunication means enabling control data to be communicated between thecamera unit and the lens unit. The camera unit and the lens unit areconfigured so as to communicate lens data information, various pieces ofcontrol information, or status information unique to a lens via thecommunication means, whereby the operation on the lens unit side can becontrolled from the camera unit side.

The above-described configuration in which a camera unit can becommunicated with a lens unit is described, for example, in JP 4(1992)-280239 A. In a camera system with an exchangeable lens systemdescribed in JP 4 (1992)-280239 A, in order for various kinds of lensunits to be used, when a lens unit is mounted on a camera unit, settinginformation (lens data) set uniquely with respect to a lens istransmitted to the camera unit. On the camera unit side, various kindsof settings suitable for the lens unit mounted on the camera unit areperformed based on the lens data transmitted from the lens unit.

Furthermore, JP 2005-173314 A discloses a configuration in which acamera system is set based on the mounting history of an accessory.Specifically, when an accessory such as an exchangeable lens is mountedon a camera unit, the camera unit obtains identification informationfrom the accessory. The camera unit determines whether or not theaccessory has been mounted previously, based on the identificationinformation obtained from the accessory. In the case of determining thatthe accessory has been mounted previously, the camera unit applies thesettings of the camera system with respect to the accessory that wasmounted previously to the current settings.

However, according to the above-mentioned conventional configuration,when the lens unit is mounted on the camera unit, or when the cameraunit with the lens unit mounted thereon is switched on, the camera unitperforms processing of acquiring lens data from the lens unit, so thatit takes a long time to obtain a photographable state from the time atwhich the lens unit is mounted on the camera unit or the time at whichthe camera unit is switched on. This lets a shutter chance slip away,causing a decrease in ease of operation.

More specifically, the conventional camera unit performs processing ofacquiring lens data that is information unique to a lens from the lensunit every time the camera unit is switched on. The camera unit performsa setting such as autofocusing control, autoexposure control, or zoomcontrol, based on the lens data acquired from the lens unit. Thetransmission/reception of lens data and the settings in the camera unitas described above are performed every time the camera unit is switchedon, so that there is a problem that the state cannot be shifted to aphotographable state immediately after the camera system is switched on.

Furthermore, a high-performance exchangeable lens has a large amount oflens data. When the amount of lens data is large, it takes a long timefor the transmission/reception of lens data between the camera unit andthe lens unit, which slows down the start-up of the camera system.Particularly, according to the configuration in which lens data istransmitted to the camera unit every time the camera system is switchedon as in the prior art, and various kinds of settings are performed inthe camera unit, the start-up of the camera system becomes much slower.

SUMMARY OF THE INVENTION

Therefore, with the foregoing in mind, it is an object of the presentinvention to provide a camera apparatus in which a shift time fromswitch-on to a photographable state is shortened to enhance the ease ofoperation. It is another object of the present invention to provide acamera system to which the camera apparatus is applied.

In order to solve the above-mentioned problems, a camera apparatus witha first configuration of the present invention is configured so that alens unit is attachable/detachable, the lens unit containing at least alens and an iris, and containing a memory storing setting informationrequired for operating the lens and the iris. The apparatus includes: acommunication part capable of communicating data with respect to thelens unit; a mounting detector that monitors attachment/detachment ofthe lens unit, and outputs first detection information when the lensunit is mounted; a controller capable of acquiring the settinginformation from the lens unit via the communication part and outputtingsecond detection information when acquiring the setting information; afirst storage that stores either the first detection informationoutputted from the mounting detector or the second detection informationoutputted from the controller; and a second storage capable of storingthe setting information acquired in the controller. The controllerchecks detection information stored in the first storage at a time ofstart-up of the camera apparatus. When the first detection informationis stored in the first storage, the controller controls so that thesetting information is acquired from the lens unit, and when the seconddetection information is stored in the first storage, the controllercontrols so that the setting information is acquired from the secondstorage.

A camera apparatus with a second configuration of the present inventionis configured so that a lens unit, with a memory storing settinginformation required for operating a lens and an iris mounted thereon,is attachable/detachable, and includes a power cut-off function ofcutting-off at least a power supply to the lens unit when anon-operation period continues for a predetermined period of time. Theapparatus includes: a communication part capable of communicating datawith respect to the lens unit; a mounting detector that monitorsattachment/detachment of the lens unit, and outputs first detectioninformation when the lens unit is mounted; a controller capable ofacquiring the setting information from the lens unit via thecommunication part and outputting second detection information whenacquiring the setting information; a first storage that stores eitherthe first detection information outputted from the mounting detector orthe second detection information outputted from the controller; and asecond storage capable of storing the setting information acquired inthe controller. The controller checks detection information stored inthe first storage when the power cut-off function is stopped to start apower supply to the lens unit. When the first detection information isstored in the first storage, the controller controls so that the settinginformation is obtained from the lens unit, and when the seconddetection information is stored in the first storage, the controllercontrols so that the setting information is acquired from the secondstorage.

A camera apparatus with a third configuration of the present inventionis configured so that a lens unit is attachable/detachable, the lensunit having a memory mounted thereon, the memory storing settinginformation required for operating a lens and an iris and identificationinformation for identifying each lens unit. The apparatus includes: acommunication part capable of communicating data with respect to thelens unit; a controller capable of acquiring the identificationinformation and the setting information from the lens unit via thecommunication part; and a second storage that previously storesidentification information corresponding to various kinds of lens unitsand setting information corresponding to the identification information.At a time of start-up of the camera apparatus, the controller acquiresthe identification information from the lens unit, and checks whether ornot identification information matched with the acquired identificationinformation is stored in the second storage. When the identificationinformation is stored in the second storage, the controller controls sothat setting information corresponding to the identification informationis read from the second storage, and when the identification informationis not stored in the second storage, the controller controls so that thesetting information is acquired from the lens unit.

A camera apparatus with a fourth configuration of the present inventionis configured so that a lens unit, with a memory storing settinginformation required for operating a lens and an iris and identificationinformation for identifying each lens unit mounted thereon, isattachable/detachable. The apparatus includes: a communication partcapable of communicating data with respect to the lens unit; a mountingdetector that monitors attachment/detachment of the lens unit, andoutputs first detection information when the lens unit is mounted; acontroller capable of acquiring the identification information and thesetting information from the lens unit via the communication part andoutputting second detection information when acquiring theidentification information and the setting information; a first storagethat stores either the first detection information outputted from themounting detector or the second detection information outputted from thecontroller; and a second storage which previously stores identificationinformation corresponding to various kinds of lens units and settinginformation corresponding to the identification information, and whichis capable of storing the setting information acquired from the lensunit. At a time of start-up of the camera apparatus, the controlleracquires the identification information from the lens unit, and checkswhether or not identification information matched with the acquiredidentification information is stored in the second storage. When theidentification information is stored in the second storage, thecontroller reads setting information corresponding to the identificationinformation from the second storage, and when the identificationinformation is not stored in the second storage, the controller checksdetection information stored in the first storage, when the firstdetection information is stored in the first storage, acquires settinginformation from the lens unit, and when the second detectioninformation is stored, acquires setting information from the secondstorage.

According to the camera apparatus and camera system of the presentinvention, the transmission operation of unique information or settinginformation from the lens unit to the camera unit at a time of start-upof the lens unit can be omitted in accordance with the state of the lensunit or the camera unit. Therefore, the lens unit can be started upquickly. Thus, in the camera unit, a shift time from switch-on to aphotographable state can be shortened to enhance ease of operation.

Furthermore, in the case where a lens is started up from a state wherethe supply of power to the lens is stopped for power saving (a so-calledsleep state of the camera unit and a power-off state of the lens unit),and photographing is performed, the start-up time of the camera systemcan be shortened. Therefore, there is a great effect that photographingcan be performed without letting a photo opportunity slip away.

Furthermore, when the lens unit is mounted on the camera unit, thecamera unit does not need to read identification information on the lensunit and can determine the configuration of a lens only based on theinformation of the mounting detector without performing communication.Therefore, there is a great effect that the camera system can speed upthe start-up of a lens.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the configuration of a camera systemin Embodiment 1.

FIG. 2 is a flowchart illustrating the start-up operation of a cameramicrocomputer in Embodiment 1.

FIG. 3 is a flowchart illustrating the operation of a sub-microcomputerin Embodiment 1.

FIG. 4 is a flowchart illustrating the operation at a time when thecamera microcomputer in Embodiment 1 is in a sleep state.

FIG. 5 is a flowchart illustrating the start-up operation of a cameramicrocomputer in Embodiment 2.

FIG. 6 is a flowchart illustrating the start-up operation of a cameramicrocomputer in Embodiment 3.

DETAILED DESCRIPTION OF THE INVENTION Embodiment 1 1. Configuration of aCamera System

FIG. 1 is a block diagram showing a configuration of a camera system ofan exchangeable lens system in the present embodiment. As shown in FIG.1, the camera system of the present embodiment is composed of a lensunit 400 and a camera unit 420.

The lens unit 400 includes a zoom lens 401, a focus lens 402, an iris403, a focus motor 404, an iris motor 405, a focus motor driver 406, aniris motor driver 407, a lens microcomputer 408, a zoom encoder 409, afocus encoder 410, an iris encoder 411, a memory 412, and a firstcommunication terminal 413 a.

The lens microcomputer 408 can control the driving of the focus motor404 via the focus motor driver 406. This enables the focus motor 404 tooperate the focus lens 402. Furthermore, the lens microcomputer 408 cancontrol the driving of the iris motor 405 via the iris motor driver 407.This enables the iris motor 405 to operate the iris 403. Furthermore,the lens microcomputer 408 arithmetically obtains operation amounts ofthe focus lens 402 and the iris 403, based on the positional informationof the focus lens 402 detected by the focus encoder 410, and thepositional information of the iris 403 detected by the iris encoder 411.Furthermore, the lens microcomputer 408 can perform serial communicationwith respect to a camera microcomputer 431 via the first communicationterminal 413 a and a second communication terminal 413 b. Furthermore,the lens microcomputer 408 controls the driving of the focus motordriver 406 and the iris motor driver 407, based on a command having adriving parameter transmitted from the camera microcomputer 431.Furthermore, the lens microcomputer 408 can transmit various pieces ofinformation (an iris value, a defocus value, etc.) of the lens unit 400to the camera microcomputer 431 by serial communication.

The memory 412 is composed of a non-volatile memory such as anelectronically erasable and programmable read-only memory (EEPROM). Thememory 412 stores setting information (hereinafter, referred to as “lensdata”) required for controlling the operation of the lens unit 400. Thelens data is unique to the lens unit, and is set on the basis of thekind and type number of the lens unit 400. The lens data stored in thememory 412 contains information such as an iris value and a defocusamount. The data stored in the memory 412 is not limited to only lensdata, and may be unique information containing other information as wellas lens data. The detailed description of the lens data will be madelater.

The zoom lens 401 is moved along an optical axis direction when a zoomring (not shown) is rotated by a user. The zoom lens 401 moves along theoptical axis direction, whereby an optical image to be incident can beenlarged or reduced. The position of the zoom lens 401 is read by thezoom encoder 409. The positional information read by the zoom encoder409 is transmitted to the lens microcomputer 408. The zoom lens 401 maybe configured so as to be moved electrically by a driving source such asa motor, instead of being configured so as to be moved manually byoperating the zoom ring.

The focus lens 402 is moved along the optical axis direction by thefocus motor 404. As a result of the movement of the focus lens 402 to apredetermined position, an optical image can be focused. The operationof the focus motor 404 is controlled by the focus motor driver 406 sothat the focus lens 402 can move in a predetermined movement directionby a predetermined movement amount. Furthermore, the position of thefocus lens 402 is read by the focus encoder 410. The positionalinformation read by the focus encoder 410 is transmitted to the lensmicrocomputer 408.

The iris 403 is operated by the iris motor 405, whereby the passagelight amount thereof is increased/decreased. The operation of the irismotor 404 is controlled by the iris motor driver 407 so that the iris410 achieves a predetermined iris amount. Furthermore, the iris amountof the iris 403 is detected by the iris encoder 405. The iris amountinformation detected by the iris encoder 405 is transmitted to the lensmicrocomputer 408.

The camera unit 420 includes a shutter 421, a CCD 422 that is an imagepickup element, a signal processor 423, an interface part 424, aninformation medium 425, a shutter controller 426, a photometric part427, a focal point detector 428, a display controller 429, a liquidcrystal display part 430, a camera microcomputer 431, a memory 432, amounting detector 433, a sub-microcomputer 434, a battery 435, a powerswitch 436, a shutter switch 437, various kinds of key switches 438, andthe second communication terminal 413 b. Furthermore, the camera unit420 has a mechanism in which the lens unit 400 is attachable/detachable.When the lens unit 400 is mounted on the camera unit 420, the firstcommunication terminal 413 a and the second communication terminal 413 bare connected to each other electrically, and data can be communicatedbetween the lens unit 400 and the camera unit 420.

The camera microcomputer 431 controls the operation of each part of thecamera system. Furthermore, the camera microcomputer 431 measures adistance with an existing algorithm and arithmetically obtains a lensdriving amount, based on an A/D value outputted from adistance-measuring sensor. The information on the arithmeticallyobtained lens driving amount is transmitted to the lens microcomputer408 via the second communication terminal 413 b and the firstcommunication terminal 413 a. Furthermore, the camera microcomputer 431controls a motor (not shown) for mirror-up or mirror-down, based on acontrol signal. Furthermore, the camera microcomputer 431 can write thelens data transmitted from the lens microcomputer 408 in the memory 432,and read the lens data stored in the memory 432. Furthermore, the cameramicrocomputer 431 can perform the control of switching on/off the cameraunit 420 and the lens unit 400, the control of operating a shutter, thecontrol of various kinds of operations based on various kinds of keymanipulations, and the like, due to the control from thesub-microcomputer 434. Furthermore, the camera microcomputer 431transmits/receives a signal with respect to each part via a bus 439.

The display controller 429 controls so as to display a battery remainingamount of the camera system, a photographing number, a TV value (shutterspeed value), an AV value (an iris value), an exposure correction value,and the like on the display part 430. In the present embodiment,although the display part 430 is composed of a liquid crystal displayelement, it may be composed of another display element as long as it candisplay similar information. Furthermore, in the present embodiment,although only the above-mentioned various pieces of information aredisplayed on the display part 430, the display part 430 may be composedof a color liquid crystal display element so that a video signal (athrough image, a photographed image, etc.) outputted from the signalprocessor 423 is displayed together with the above-mentioned variouspieces of information.

The focal point detector 428 includes a line sensor for autofocusing(hereinafter, referred to as “AF”) by an existing phase differencedetection system, and a circuit unit for accumulation and reading of theline sensor. The operation of the focal point detector 428 is controlledby the camera microcomputer 431.

The photometric part 427 performs the measurement of a light amount(photometric measurement) in an object by the operation control from thecamera microcomputer 431. The information on the light amount measuredin the photometric part 427 is transmitted to the camera microcomputer431.

The shutter controller 426 controls the traveling of a front curtain anda rear curtain in the shutter 421. Specifically, the shutter controller426 controls the operation of the shutter 421 so that the front curtainand the rear curtain can travel at a shutter speed that isarithmetically obtained by the camera microcomputer 431.

The sub-microcomputer 434 is supplied with power at all times by thebattery 435, and hence, is operated even when the camera unit 420 isswitched off. Furthermore, a memory is contained in thesub-microcomputer 434, and at least a lens flag is stored in the memory.The lens flag is set to be “1” when the camera unit 420 acquires lensdata from the lens unit 400, and the acquired lens data is written inthe memory 432. Furthermore, the lens flag is cleared to “0” when theattachment/detachment between the lens unit 400 and the camera unit 420is detected in the mounting detector 433. Furthermore, thesub-microcomputer 434 reads the states of the power switch 436, theshutter switch 437, the various kinds of key switches 438, and themounting detector 433, and instructs the camera microcomputer 431 to beoperated.

The power switch 436 starts the operation of the camera system. Uponrecognizing that the power switch 436 is turned on, thesub-microcomputer 434 transmits a command for starting the measurementof light, the measurement of a distance, display, and the like to thecamera microcomputer 431.

The shutter switch 437 is synchronized with a release button of thecamera system. Upon recognizing that the shutter switch 437 is turnedon, the sub-microcomputer 435 transmits a command for starting anexposure operation to the camera microcomputer 431.

The various kinds of key switches 438 are composed of a switch forswitching a mode (a TV priority mode, an AV priority mode, a manualoperation mode, a program mode, etc.) of a camera, a switch for settingan AF mode (a one-shot AF, a servo AF for focusing an object at alltimes, etc.), a switch for switching and setting a photometricmeasurement mode (evaluation metering, centerweighted metering, partialmetering, spot metering, etc.). Upon recognizing that the various kindsof switches are operated, the sub-microcomputer 434 instructs the cameramicrocomputer 431 to operate each function, thereby executing variouskinds of functions.

The mounting detector 433 detects the attachment/detachment of the lensunit 400 with respect to the camera unit 420. A detection signaldetected by the mounting detector 433 is outputted to thesub-microcomputer 434.

The shutter 421 is composed of a front curtain and a rear curtain whoseoperations are controlled by the shutter controller 426. The shutter 421moves across an optical axis, thereby causing an optical image incidentvia the lenses 401, 402 and the iris 403 to be incident upon the CCD 422for a predetermined period of time.

The CCD 422 converts the optical image to be incident into an electricsignal and outputs it. Although the CCD 422 is composed of a CCD imagesensor in the present embodiment, it may be composed of another imagepickup element such as a CMOS image sensor.

The signal processor 423 performs various kinds of signal processes suchas analog-digital conversion, adjustment of image quality, imagecompression, and the like with respect to the electric signal outputtedfrom the CCD 422, and outputs image data.

The interface part 424 records image data outputted from the signalprocessor 423 on the information medium 425. The operation of theinterface part 424 is not limited to recording of image data on theinformation medium 425, and the interface part 424 also can read imagedata recorded on the information medium 425.

The information medium 425 is composed of, for example, a memory cardcontaining a semiconductor memory. The information medium 425 may becomposed of another medium such as a disk-shaped recording medium, aslong as at least a digital image can be recorded thereon.

2. Operation of a Camera System [2-1. Basic Operation]

The description of a basic operation is predicated on the lens unit 400being mounted on the camera unit 420.

In FIG. 1, first, when the power switch 436 is operated by a user so asto be turned on, the sub-microcomputer 434 outputs a start-up command tothe camera microcomputer 431. The camera microcomputer 431 starts upeach part in the camera unit 420 based on the inputted start-up command.Furthermore, the camera microcomputer 431 output a start-up command tothe lens microcomputer 408 via the second communication terminal 413 band the first communication terminal 413 a. The lens microcomputer 408controls so as to start up the lens unit 400 based on the inputtedstart-up command. The lens microcomputer 408 outputs lens data stored inthe memory 412 to the camera microcomputer 431.

The lens microcomputer 408 controls the focus motor driver 406 so as tomove the focus lens 402 to a predetermined position with a commandhaving a driving parameter transmitted from the camera microcomputer431. Furthermore, the lens microcomputer 408 controls the iris motordriver 407 so that the iris 403 achieves a predetermined iris amountwith the command having a driving parameter transmitted from the cameramicrocomputer 431.

Next, when the shutter switch 437 is operated by the user, thesub-microcomputer 434 outputs information indicating that the shutterswitch 437 is operated to the camera microcomputer 431. Next, the cameramicrocomputer 431 controls a motor (not shown) of mirror-up, and afterthe mirror-up, controls the shutter controller 426 so that the shutter421 is operated. The shutter controller 426 causes the front curtain andthe rear curtain of the shutter 421 to travel at a predetermined timing.Due to the operation of the shutter 421, an optical image having passedthrough the zoom lens 401, the focus lens 402, and the like is incidentupon the CCD 422 for a predetermined period of time.

The CCD 422 converts the incident optical image into an electric signaland outputs it. The electric signal outputted from the CCD 422 isinputted to the signal processor 423. The signal processor 423 performssignal processes such as analog-digital conversion, adjustment of imagequality, image compression, and the like to the inputted electricsignal. Image data after being subjected to the signal processing isstored on the information medium 425 via the interface part 424. Theimage data to be stored on the information medium 425 also can be storedas it is, without being compressed in the signal processor 423.

Furthermore, when the zoom ring is operated by the user so as to performzooming, the zoom lens 401 is moved along the optical axis direction,and an optical image formed on the CCD 422 can be enlarged or reduced.

Furthermore, when the user presses the shutter switch 437 halfway downto perform autofocusing, the camera microcomputer 431 arithmeticallyobtains a movement direction and a movement amount of the focus lens 402based on the focus information detected in the focal point detector 428.The information arithmetically obtained in the camera microcomputer 431is inputted to the lens microcomputer 408 via the second communicationterminal 413 b and the first communication terminal 413 a. The lensmicrocomputer 408 controls the focus motor driver 406 so that the focuslens 402 is moved, based on the inputted information. The focus motordriver 406 drives the focus motor 404 to operate the focus lens 402 sothat the optical image formed on the CCD 422 is focused.

Furthermore, in the iris adjustment, the camera microcomputer 431arithmetically obtains an iris amount based on the object light amountdetected by the photometric part 427. The information arithmeticallyobtained by the camera microcomputer 431 is outputted to the lensmicrocomputer 408, and the lens microcomputer 408 controls the irismotor driver 407. The iris motor driver 407 operates the iris motor 405to adjust the opening of the iris 403.

[2-2. Operation of the Camera Microcomputer 431]

FIG. 2 is a flowchart illustrating the operation of the cameramicrocomputer 431.

First, when the camera unit 420 is switched on (Step S101), the cameramicrocomputer 431 is started up (Step S102).

Next, the camera microcomputer 431 initializes the internal setting ofthe camera unit 420. Specifically, the camera microcomputer 431 sets theselection state and setting state of operation switches such as theshutter switch 437 and the various kinds of key switches 438 inpreviously determined initial states (Step S103).

Next, the camera microcomputer 431 checks the state of the mountingdetector 433, and determines whether or not the lens unit 400 is mounted(Step S104). Then, upon determining that the lens unit 400 is notmounted, the camera microcomputer 431 executes various kinds offunctions of the camera unit 420 based on the various kinds of keyswitches 438 (Step S105).

On the other hand, when the camera microcomputer 431 determines that thelens unit 400 is mounted (Step S104), the camera microcomputer 431supplies power to the lens unit 400 via a communication contact terminal413. When the lens unit 400 is supplied with power, the lensmicrocomputer 408 is started up.

Next, the camera microcomputer 431 initializes the lens unit 400.Specifically, the lens microcomputer 408 controls the focus motor driver406 to move the focus lens 402 to an initial position. Furthermore, thelens microcomputer 408 controls the iris motor driver 407 to shift theiris 403 to an initial state (Step S106).

Next, the camera microcomputer 431 outputs a command for requesting lensspecifying data with respect to the lens microcomputer 408. The lensmicrocomputer 408 reads lens specifying data from the memory 412 inaccordance with the inputted command, and outputs it to the cameramicrocomputer 431. The camera microcomputer 431 writes the acquired lensspecifying data in the memory 432. The contents of the lens specifyingdata will be described in detail later (Step S115).

Next, the camera microcomputer 431 checks the state of a lens flag setin the sub-microcomputer 434, and determines whether or not the lensunit 400 has been attached/detached after the previous acquisition oflens data (Step S107). When the mounting detector 433 detects that thelens unit 400 has been attached/detached, the sub-microcomputer 434clears the lens flag to “0”. Furthermore, when the sub-microcomputer 434recognizes that the camera microcomputer 431 acquired lens data from thelens unit 400 side via the first communication terminal 413 a and thesecond communication terminal 413 b, it sets the lens flag to “1”. Thus,as a result of the determination in Step S107, when the lens unit 400has not been attached/detached after the timing of the previousacquisition of lens data, the lens flag remains at “1”, so that theprocess proceeds to Step S114. On the other hand, when the lens unit 400has been attached/detached even once after the timing of the previousacquisition of lens data, the lens flag is cleared to “0”, so that theprocess proceeds to Step S108.

As a result of the determination in Step S107, when the lens flag set inthe sub-microcomputer 434 is cleared to “0”, the camera microcomputer431 outputs a command for requesting lens data with respect to the lensmicrocomputer 408 in the lens unit 400. The lens microcomputer 408outputs lens data stored in the memory 412 to the camera microcomputer431 via the first communication terminal 413 a and the secondcommunication terminal 413 b in accordance with the inputted request(Step S108).

Next, the camera microcomputer 431 stores the lens data acquired fromthe lens microcomputer 408 in the memory 432. Furthermore, uponrecognizing this, the sub-microcomputer 434 sets the lens flag in thesub-microcomputer 434 to “1”. Furthermore, the camera microcomputer 431controls the operation of the lens unit 400 based on the lens dataacquired from the lens microcomputer 408. Furthermore, the cameramicrocomputer 431 can shift the camera unit 420 to a state where aphotographing operation can be performed (Step S109).

On the other hand, as a result of the determination in Step S107, whenthe lens flag set in the sub-microcomputer 434 is set to “1”, the lensdata stored in the memory 432 is read without performing thecommunication between the lens unit 400 and the camera unit 420. Thecamera microcomputer 431 controls the operation of the lens unit 400based on the lens data read from the memory 432. Furthermore, the cameramicrocomputer 431 can shift the camera unit 420 to a state where aphotographing operation can be performed (Step S114).

Thus, when the lens flag is set to “1” at a time when the camera systemis switched on, the operation of acquiring lens data with respect to thelens unit 400 and the operation of storing the lens data in the memory432 are not performed, so that the camera system can be started up in ashort period of time after the lens unit 400 is supplied with power, andvarious kinds of functions can be shifted to an executable state.

Next, the camera microcomputer 431 counts a non-operation time of thecamera system with a counter, and determines whether or not thenon-operation time has reached a predetermined time (for example, 5minutes). More specifically, it is detected that the camera system hasnot been operated for a predetermined period of time. When the camerasystem is operated by the time the value of the counter reaches apredetermined time, the counter is reset, and the process proceeds toStep S111. When the value of the counter reaches a predetermined time,the process proceeds to Step S112 (Step S110).

When the camera system is operated by the time the value of the counterreaches a predetermined time, the camera microcomputer 431 can executevarious kinds of functions in accordance with the states of the powerswitch 436, the shutter switch 437, and the various kinds of keyswitches 438. More specifically, an object is photographed by operatingthe shutter switch 437, and a functional operation such as white balanceadjustment can be performed by operating the key switches 438 (Step111).

On the other hand, when the value of the counter reaches a predeterminedtime, the camera microcomputer 431 performs lens completion processingto stop the supply of power to the lens unit 400 (Step S112).

Next, the camera microcomputer 431 is shifted to a sleep state. The“sleep state” refers to the state in which the operations of a lensunit, an image pickup system, a display part, and the like are stoppedwhen the camera unit is not operated temporarily when the power switchof the camera unit is in an ON state (Step S113).

When the camera microcomputer 431 is in a sleep state, the supply ofpower to each part in the camera unit 420 is stopped or reduced, andhence, various kinds of operations such as photographing cannot beperformed. In order to return the sleep state to the normal state, forexample, the power switch 436 is operated to newly switch on the camerasystem, or the shutter switch 437 or various kinds of key switches 438are operated. The operation of the camera microcomputer 431 when thesleep state is returned to the normal state will be described later withreference to FIG. 4.

[2-3. Operation of the Sub-Microcomputer 434]

FIG. 3 is a flowchart illustrating an operation of the sub-microcomputer434. The sub-microcomputer 434 is operated by being supplied with powerfrom the battery 435, when the camera unit 420 is switched on andoperates normally or it is in a sleep state.

First, the sub-microcomputer 434 checks the state of the mountingdetector 433 (Step S201). Upon recognizing that the lens unit 400 isattached/detached with respect to the camera unit 420, thesub-microcomputer 434 clears the lens flag in the memory to “0” (StepS202). Furthermore, in the mounting detector 433, when theattachment/detachment of the lens unit 400 is not detected, thesub-microcomputer 434 does not change the lens flag in the memory.

Next, the sub-microcomputer 434 notifies the camera microcomputer 431 ofthe state of the mounting detector 433 (Step S203).

Next, the sub-microcomputer 434 checks the state of the power switch 436(Step S204). Upon recognizing that the power switch 436 is changed froman ON state to an OFF state, the sub-microcomputer 434 instructs thecamera microcomputer 431 to perform the processing of switch-on, and theprocess returns to Step S201.

Furthermore, upon recognizing that the power switch 436 is changed froman OFF state to an ON state, the sub-microcomputer 434 instructs thecamera microcomputer 431 to perform the processing of switch-on (StepS205).

Next, when the power switch 436 is switched on, the sub-microcomputer434 checks the state of the shutter switch 437 (Step S206). Uponrecognizing that the shutter switch 437 is switched on, thesub-microcomputer 434 proceeds to Step S207. On the other hand, uponrecognizing that the shutter switch 437 is not switched on (i.e., in thecase where the shutter switch 437 is not operated), thesub-microcomputer 434 proceeds to Step S208.

When the shutter switch 437 is turned on, the sub-microcomputer 434transmits an instruction of starting an exposure operation to the cameramicrocomputer 431 as the processing of switching on a shutter. Thecamera microcomputer 431 starts an exposure operation and performsphotographing processing in accordance with the instruction from thesub-microcomputer 434 (Step S207).

Next, the sub-microcomputer 434 checks the states of the various kindsof key switches 438 (Step S208). Upon detecting that the states of thevarious kinds of key switches 438 have changed, the sub-microcomputer434 instructs the camera microcomputer 431 to perform processingcorresponding to the states of the various kinds of keys. The cameramicrocomputer 431 performs various processes in accordance with theinstruction from the sub-microcomputer 434 (Step S209).

After the processing in Step S209, or when no change of the state of thekey switches 438 is detected in Step S208, the process returns to StepS201. The sub-microcomputer 434 repeats these processes, therebyperforming ordinary loop processing.

[2-4. Operation in a Sleep State]

FIG. 4 is a flowchart illustrating the operation of the cameramicrocomputer 431 in a sleep state. In FIG. 4, the same steps as thosein FIG. 2 are denoted with the same reference numerals as those therein,and the detailed description thereof will be omitted.

First, the sub-microcomputer 434 checks whether or not the operations ofthe power switch 436 and the shutter switch 437 have been performed whenthe camera system is in a sleep state. When the operations have beenperformed, the process proceeds to Step S102 (Step S301).

Next, the camera microcomputer 431 is started up based on a start-upcommand inputted from the sub-microcomputer 434. The cameramicrocomputer 431 controls so that each part in the camera unit 420 isstarted up. The state setting of the camera unit is held even in a sleepstate, so that the initialization processing of the camera unit 420 isnot performed.

The processes after Step S104 are the same as those after Step S104 inFIG. 2, so that the operation description thereof will be omitted. Morespecifically, if the lens wilt 400 is not attached/detached with respectto the camera unit 420 in a sleep state, lens data is not acquired, sothat the camera system can be started up at a high-speed, and shifted toa photographable state.

3. Contents of Data

Table 1 shows the contents of lens specifying data acquired by thecamera microcomputer 431 from the lens microcomputer 408 in Step S115 inFIGS. 2 and 4.

TABLE 1 Method Data No. Lens data item for using lens data in a body ALens identification data Lens unique information such aspresence/absence of an iris ring and presence/absence of an opticalshaking correction function B Manufacturer ID Use for identifying a lensunit C Lens ID Use for identifying a lens unit D Lens name Use foridentifying a lens unit

In Table 1, the data A relates to the specification of the lens unit400, and contains information on the presence/absence of an iris ring,the presence/absence of an optical shaking correction function, and thelike. The Data B is an ID of a manufacturer of the lens unit 400. Thedata C is an ID of the lens unit 400. The data D contains information onthe name of the lens unit 400.

As shown in Table 1, the lens specifying data contains informationcapable of specifying the kind and type of the lens unit, such as thelens identification data and the lens ID. This enables the cameramicrocomputer 431 to identify a lens unit mounted on the camera unit420.

Furthermore, Tables 2 and 3 show lens data acquired by the cameramicrocomputer 431 from the lens unit 400, or lens data acquired by thecamera microcomputer 431 from the memory 432 in Steps S108 and S114 inFIGS. 2 and 4. The lens data shown in Tables 2 and 3 are referred to as“characteristics data”.

TABLE 2 Data No. Lens data item Method for using lens data in a body AResolution number of Number of zoom positions having lens a zoom encoderdata from a wide-angle end to a telephoto end B Resolution number ofNumber of focus positions having lens a focus encoder data from aninfinite distance to a close distance C Focal length Focal length in awide-angle end of a (wide-angle end) zoom lens (mm) D Focal length Focallength in a telephoto end of a zoom (telephoto end) lens (mm)

TABLE 3 Data No. Lens data item Method for using lens data in a body AFocal length Focal length at each zoom position (mm) B Opened iris value(AV value) Iris value for each zoom position in an iris open state CMinimum iris value (AV value) Iris value for each zoom position in aniris minimum state D Opened iris value at a time of Use for AE controlphotometric measurement (AV value) E Focusing threshold Focusing isdetermined based on whether or not a defocus amount is in a range of afocusing thresh at a time of AF control F Pulse number between an Drivea focus lens within a pulse number infinite position and a close at atime of AF control position G Closest photographing Photographabledistance at a closest distance position (mm) H AF correction value Usefor AF correction

In Table 2, the data A is the number of zoom positions from a telephotoend to a wide-angle end of the zoom lens 401 in the lens unit 400. Thedata B is the number of focus positions from an infinite position to aclose position of the focus lens 402. The data C is data on a focallength at a wide-angle end of the zoom lens 401. The data D is data on afocal length at a telephoto end of the zoom lens 401.

The characteristics data shown in Table 3 are set so as to correspond torespective zoom encoder positions (zoom positions) divided by a zoomencoder division number represented by the data A in Table 2. Forexample, when the zoom encoder division number represented by the data Ain Table 2 is “32”, 32 kinds of patterns are set in the characteristicsdata shown in Table 3.

In Table 3, the data A is data on a focal length at each zoom encoderposition of the zoom lens 401. The data B is an iris value (AV value) ata time when the iris 403 is opened. The data C is an iris value (AVvalue) at a time when the iris 403 is in a minimum state. The data B andC represent iris values at a time of photographing. The data D is anopened iris value at a time of photometric measurement, which is an irisvalue used for controlling an auto exposure (AE). The data E is areference value (focusing threshold) for determining a focused state ata time of AF control. More specifically, the data E is a value fordetermining a focused state by comparing a defocus amount with areference value at a time of AF control, and determining whether or notthe defocus amount is in the range of the reference value. The range ofthe value of the data E increases as a zoom angle increases. The data Fis the number of pulses from an infinite position to a dose position ofthe focus lens 402. The data G is a distance at which an object can bephotographed at a closest position, which is a distance from the objectto an image pickup plane of the CCD 422. The data H is a value forcorrecting an error at a time of AF control, caused by a displacement interms of an optical design of the focus lens 402.

The camera microcomputer 431 determines methods for controlling a focusand controlling an iris based on the characteristics data shown inTables 2 and 3.

Furthermore, the camera microcomputer 431 acquires a parameter(hereinafter, referred to as lens state data) regarding the currentstate of the lens unit 400 periodically from the lens unit 400. Table 4shows lens state data acquired by the camera microcomputer 431 from thelens unit 400.

TABLE 4 Data No. Lens data item Method for using lens data in a body ACurrent lens state Use for notification of an operation state of a lensunit B Current zoom position Use for controlling the driving of a lensand an iris C Current iris value Use for controlling the driving of aniris D Current focus lens Use for controlling the driving of a lensposition

In Table 4, the data A represents the current state of the lens unit400. For example, the data A contains information such as “the focuslens 402 is being driven”, “the iris 403 is being driven”, and “the zoomlens 401 is positioned at a telephoto end or a wide-angle end”. The dataB represents the current zoom encoder position (zoom position). The dataC is data on a current iris value. The data D represents the currentposition of the focus lens 402.

As shown in Table 4, the lens state data contains the current operationstate of the lens unit 400, a zoom position, an iris value, and thelike. The lens state data changes in accordance with the operation ofthe lens unit 400. The lens specifying data, characteristics data, andlens state data are not limited to those shown respectively in Tables.

In the case were the camera system is switched on, or in the case wherea key operation is performed when the camera system is in a sleep state,the camera microcomputer 431 acquires the lens specifying data shown inTable 1 from the lens unit 400, and acquires characteristics data shownin Table 2 from the lens unit 400 or the memory 432. This enables thecamera microcomputer 431 to shift the camera system to a photographablestate.

Furthermore, when the camera system is placed in a photographable state,the camera microcomputer 431 acquires lens state data shown in Table 4from the lens unit 400. The camera microcomputer 431 determines asubsequent control command regarding focus control and iris control,based on the characteristics data shown in Tables 2 and 3, and the lensstate data shown in Table 4. This enables the camera microcomputer 431to perform focus control and iris control of the lens unit 400. Althoughthe lens data shown in Tables 1 to 4 are data for performing focuscontrol and iris control, they may contain lens data for performing zoomcontrol.

4. Effects of an Embodiment, Etc.

As described above, according to the present embodiment, when the lensunit 400 has not been attached/detached after the previous acquisitionof lens data when the power switch 436 of the camera system is shiftedfrom an OFF state to an ON state, the start-up of the camera system canbe sped up. More specifically, when the camera system is switched on,first, it is checked whether the lens unit 400 has beenattached/detached after the previous acquisition of lens data. In thecase where the lens unit 400 has not been attached/detached, the cameramicrocomputer 431 is operated based on the lens data stored in thememory 432, without acquiring lens data (lens specifying data andcharacteristics data). This makes it unnecessary for the camera unit 420to acquire lens data from the lens unit 400 and write the acquired lensdata in the memory 432, whereby the start-up of the camera system can besped up.

In particular, the effect of a high-speed start-up is effective for auser who rarely attaches/detaches or exchanges the lens unit 400, andleaves one lens unit mounted on the camera unit for long periods.

Furthermore, since serial communication is not performed between thecamera unit 420 and the lens unit 400, and the acquisition of lens datacan be omitted only with the determination processing in the camera unit420, the determination processing also can have a simple configuration.

Furthermore, even if the amount of lens data stored in the lens unit 400increases along with the enhancement of performance of an exchangeablelens, although the acquisition and storage of lens data are required atan initial switch-on, these processes can be omitted later. Therefore,the camera system can be started-up at a high speed.

Furthermore, in the present embodiment, one lens data corresponding toone lens unit is stored in the memory 432, so that a memory for storinglens data on a number of exchangeable lenses is not necessary, and thecost of a memory can be reduced.

Furthermore, the mechanism for selecting one lens data from a pluralityof lens data is not necessary, so that a very simple configuration canbe achieved.

Furthermore, a lens start-up time can be shortened at a time ofreturning from a sleep state, so that photographing can be performedwithout letting a photo opportunity slip away.

Furthermore, when the lens unit 400 is mounted on the camera unit 420,the camera unit 420 does not need to read identification information onthe lens unit 400, and can determine the configuration of a lens onlybased on the information of the mounting detector 433 without performingcommunication. Therefore, the start-up of a lens can be sped up.

When the lens unit 400 is attached/detached with respect to the cameraunit 420 when the camera system is in an ON state, the cameramicrocomputer 431 acquires lens data from the lens unit 400, and storesthe lens data in the memory 432.

Furthermore, in the above description, a camera system in which a lensunit can be exchanged has been described. However, the present inventionalso can be applied similarly to a camera system having the followingconfiguration: at a time of start-up of a camera, the unique informationon an accessory such as a strobe, a flash, a teleconverter, or anintermediate ring is transmitted to a camera unit, whereby the uniqueinformation is set in the camera unit.

Furthermore, although the lens control of an exchangeable lens has beendescribed regarding autofocusing control and autoexposure control, thepresent invention is not limited thereto, and other lens data on a lensfor performing optical shaking correction control, etc. may be stored inthe memory 412.

Embodiment 2

FIG. 5 is a flowchart showing an operation of a camera microcomputer ofembodiment 2. In FIG. 5, the same steps as those in the flowchart inFIG. 2 are denoted with the same reference numerals as those therein,and the detailed description thereof will be omitted.

Furthermore, the camera microcomputer of Embodiment 2 is operated basedon the block diagram shown in FIG. 1; however, the data stored in thememories 412 and 432 are different between Embodiments 1 and 2. In thememory 412 of Embodiment 2, unique information composed ofidentification information (hereinafter, referred to as a “lens ID”) setfor each lens and setting information (hereinafter, referred to as “lensdata”) containing a focus lens position, an iris amount, and the like iswritten. Furthermore, in the memory 432, a plurality of pieces of uniqueinformation, composed of a lens ID varying for each type and eachproduct no. and lens data corresponding to the lens ID, are written. Theidentification information (lens ID) in Embodiment 2 is the same as thelens specifying data in Embodiment 1. More specifically, the “lens ID”in Embodiment 2 is different from the “lens ID” in Table 1, and is thesame as the lens specifying data containing all the data in Table 1. Thesetting information (lens data) in Embodiment 2 is the same as thecharacteristics data in Embodiment 1. Thus, the unique information inEmbodiment 2 corresponds to the lens specifying data and thecharacteristics data in Embodiment 1.

Furthermore, the lens data in unique information contains informationrequired for controlling various operations of a focus, an iris, a zoom,and the like, so that the amount of the lens data is large. Inparticular, recently, various functions such as an optical shakingcorrection function are added to a lens unit to increase the data amountof setting information, and hence, the lens unit is composed of data ofseveral kilobytes. On the other hand, the lens ID is identificationinformation set for each lens, so that the lens ID is composed of asmall amount of data of several bytes. Furthermore, even if the lensunit is made multi-functional, the data amount of the lens ID does notincrease.

Furthermore, the memory 432 is composed of, for example, an EEPROM. Inthe memory 432, unique information composed of a lens ID correspondingto a lens type and product no. and lens data corresponding to the lensID are previously written at a time of shipment from a factory.Furthermore, the memory 432 also can be composed of a read-only memory(ROM). If the memory 432 is composed of a ROM, the cost can be reducedcompared with the case where the memory 432 is composed of an EEPROM.

Furthermore, the unique information previously written in the memory 432may be configured so as to be updated by a user. More specifically, thenumber of pieces of unique information increases every time a new typeis put on sale from a lens manufacturer, and in order to render thecamera unit to handle a new lens, it is necessary to update the uniqueinformation written in the memory 432. As the update method, forexample, there is a method for downloading new unique information fromthe Internet, storing the downloaded unique information on aninformation medium such as a memory card, mounting the informationmedium on the camera unit 420, and performing an update operation of thememory 432. As the method for updating unique information, there also isa method for connecting a camera system to a personal computer through acommunication cable, transferring the unique information downloaded fromthe Internet to the camera system via the communication cable, andperforming an update operation. Furthermore, the data may be updated byreplacing all the unique information in the memory 432, or addingdifferential data to the existing unique information.

In FIG. 5, first, when the camera unit 420 is switched on (Step S101),the camera microcomputer 431 is started up (Step S102).

Next, the camera microcomputer 431 initializes the internal setting ofthe camera unit 420. Specifically, the camera microcomputer 431 sets theselection state and setting state of operation switches such as thesettings of the shutter switch 437 and the various kinds of key switches438 in the camera unit in previously determined initialized states (StepS103).

Next, the camera microcomputer 431 checks the state of the mountingdetector 433, and determines whether or not the lens unit 400 is mounted(Step S104). Upon determining that the lens unit 400 is not mounted onthe camera unit 420, the camera microcomputer 431 executes various kindsof functions of the camera unit 420 based on the various kinds of keyswitches 438 (Step S105).

On the other hand, upon detecting that the lens unit 400 is mounted onthe camera unit 420, the camera microcomputer 431 supplies power to thelens unit 400 via the communication contact terminal 413, when the poweris supplied to the lens unit 400, the lens microcomputer 408 is startedup.

Next, the camera microcomputer 431 initializes the lens unit 400.Specifically, the lens microcomputer 408 controls the focus motor driver406 to move the focus lens 402 to an initial position, based on thecontrol from the camera microcomputer 431. Furthermore, the lensmicrocomputer 408 controls the iris motor driver 407 to shift the iris403 to an initial state, based on the control from the cameramicrocomputer 431 (Step S106).

Next, the camera microcomputer 431 outputs a command for requesting thelens ID with respect to the lens microcomputer 408. The lensmicrocomputer 408 reads a lens ID from the memory 412 and outputs it tothe camera microcomputer 431, in accordance with the inputted command(Step S401).

Next, the camera microcomputer 431 searches for a lens ID matched withthe lens ID acquired from the lens unit 400 in the lens IDs stored inthe memory 432. If there is a lens ID matched with the acquired lens ID,lens data corresponding to that lens ID is read from the memory 432, asshown in Step S114 (Step S402).

On the other hand, when there is no lens ID matched with the lens IDacquired from the lens unit 400 in the memory 432, lens data is acquiredfrom the lens unit (Step S108).

The subsequent processing operation is the same as that of Embodiment 1,so that the description thereof will be omitted.

As described above, according to the present embodiment, when the camerasystem is switched on, only a lens ID is acquired from the lens unit400, and when there is a lens ID matched with the acquired lens ID inthe memory 432 on the camera unit 420 side, operation control isperformed based on the lens data written in the memory 432. This makesit unnecessary to perform the processing of acquiring lens data from thelens unit 400 and the processing of writing the acquired lens data inthe memory 432, so that the start-up of the camera system can be spedup.

Furthermore, since only the lens ID that is a part of unique informationis acquired from the lens unit 400, the communication between the lensunit 400 and the camera unit 420 is completed in a short period of time,whereby the start-up of the camera system can be sped up.

Embodiment 3

FIG. 6 is a flowchart showing an operation of a camera microcomputer ofEmbodiment 3. In FIG. 3, the same steps as those in the flowcharts inFIGS. 2 and 5 are denoted with the same reference numerals as thosetherein, and the detailed description thereof will be omitted.

The camera microcomputer of Embodiment 3 is operated based on the blockdiagram shown in FIG. 1; however, the configuration of the memory 432 isdifferent between Embodiments 1 and 3. The memory 432 of the camera unit420 includes a first region capable of storing lens data (hereinafter,referred to as “first lens data”) acquired from the lens unit 400, and asecond region storing unique information composed of a lens ID and lensdata (hereinafter, referred to as “second lens data”) previously writtenat a time of shipment from a factory. In Embodiment 3, although thefirst lens data and the unique information are stored in one memory 432,the following configuration also may be possible: a rewritable memory(e.g., an EEPROM) and a read-only memory (e.g., a ROM) are providedindependently, the first lens data is stored in the rewritable memory,and the unique information is stored in the read-only memory.

As shown in FIG. 6, after the initialization processing of the lens unit(Step S106), the camera microcomputer 431 outputs a command forrequesting a lens ID with respect to the lens microcomputer 408. Thelens microcomputer 408 reads a lens ID from the memory 412 and outputsit to the camera microcomputer 431 in accordance with the inputtedcommand (Step S401).

Next, the camera microcomputer 431 searches for a lens ID matched withthe lens ID acquired from the lens microcomputer 408 in the lens IDsstored in the memory 432 (Step S402). If there is a lens ID matched withthe lens ID acquired from the lens microcomputer 408 in the memory 432,the camera microcomputer 431 reads lens data corresponding to the lensID from the memory 432.

On the other hand, when there is no lens ID matched with the lens IDacquired from the lens microcomputer 408 in the memory 432, the processproceeds to Step S107.

Next, the camera microcomputer 431 checks the state of a lens flag setin the sub-microcomputer 434, and determines whether the lens unit 400has been attached/detached from the previous acquisition of lens data(Step S107). When the mounting detector 433 detects that the lens unit400 has been attached/detached, the sub-microcomputer 434 clears a lensflag to “0”. Furthermore, when the camera microcomputer 431 acquireslens data from the lens microcomputer 408 via the first communicationterminal 413 a and the second communication terminal 413 b and stores itin memory 32. Upon recognizing this, the sub-microcomputer 434 sets thelens flag to “1”. Thus, as a result of the determination in Step S107,when the lens unit 400 has not been attached/detached after the timingof the previous acquisition of lens data, the lens flag remains at “1”,so that the process proceeds to Step S114. On the other hand, when thelens unit 400 has been attached/detached even once after the timing ofthe previous acquisition of lens data, the lens flag has been cleared to“0”, so that the process proceeds to Step S108.

Next, the camera microcomputer 431 outputs a command for requesting lensdata with respect to the lens microcomputer 408. The lens microcomputer408 outputs the lens data stored in the memory 412 to the cameramicrocomputer 431 via the first communication terminal 413 a and thesecond communication terminal 413 b, in accordance with the inputtedrequest (Step S108).

Next, the camera microcomputer 431 stores the lens data acquired fromthe lens microcomputer 408 in the memory 432. Upon recognizing this, thesub-microcomputer 434 sets the lens flag to “1”. The cameramicrocomputer 431 can control the operation of the lens unit 400, andshift the camera unit 420 to a photographable state, based on the lensdata acquired from the lens microcomputer 408 (Step S109).

The subsequent processing operation is the same as that of Embodiment 1,so that the description thereof will be omitted.

As described above, according to the present embodiment, it is notnecessary to perform the processing of acquiring lens data from the lensunit 400, and the processing of writing the acquired lens data in thememory 432, so that the start-up of the camera system can be sped up.

Furthermore, since only the lens ID that is a part of unique informationis acquired from the lens unit 400, the communication between the lensunit 400 and the camera unit 420 is completed in a short period of time,whereby the start-up of the camera system can be sped up.

In Embodiments 1-3, the lens to be mounted on the lens unit 400 is notlimited to a zoom lens, and may be a unifocal lens. In the case of theunifocal lens, only data related to a focus and an iris among the datashown in Tables 2, 3, and 4 are transmitted/received between the cameraunit 430 and the lens unit 400. In this case, the contents of the dataare essentially the same, with only the amount of each data beingreduced.

Furthermore, although Embodiments 1-3 have a configuration in which thelens flag is stored in the memory which is in the sub-microcomputer 434,the lens flag also may be stored in the camera microcomputer 431. Inthat case, a memory is configured in the camera microcomputer 431, andthe lens flag is arranged to be stored therein. Also, the operation forsetting the lens flag is done by the camera microcomputer 431.

Furthermore, although Embodiments 1-3 have a configuration in which thecamera microcomputer 431 and the sub-microcomputer 434 are individualmicrocomputers, they also may be configured as only one microcomputer.In that case, the only one microcomputer may be configured so as toperform both functions of the camera microcomputer 431 and thesub-microcomputer 434.

[Note 1]

A first camera apparatus of the present invention is a camera apparatusto which a lens unit is attachable/detachable, capable of acquiringunique information set in the lens unit, including: a communication partto which the unique information is inputted from the lens unit; astorage capable of storing the unique information inputted to thecommunication part; and a controller that controls so that the uniqueinformation is outputted to the lens unit, wherein the controllercontrols so that the unique information is acquired from the lens unitonly when an operation of attaching/detaching the lens unit isperformed.

According to the above configuration, the transmission operation ofunique information from the lens unit to the camera unit at a time ofstart-up of the lens unit can be omitted in accordance with the state ofthe lens unit or the camera unit Therefore, the lens unit can be startedup at a high speed. Thus, in the camera unit, a shift time fromswitch-on to a photographable state can be shortened to enhance ease ofoperation.

Furthermore, when the lens unit is mounted on the camera unit, thecamera unit does not need to read identification information on the lensunit and can determine the configuration of a lens only based on theinformation of the mounting detector without performing communication.Therefore, the camera system can speed up the start-up of a lensgreatly.

The unique information corresponds to lens specifying data andcharacteristics data. The communication part corresponds to the firstcommunication terminal 413 a, the second communication terminal 413 b,and means for driving them. The storage corresponds to the memory in thesub-microcomputer 434 and the memory 432. The controller corresponds tothe camera microcomputer 431.

[Note 2]

A second camera apparatus of the present invention is a camera apparatusto which a lens unit is attachable/detachable, the lens unit containingat least a lens and an iris, and containing a memory storing settinginformation required for operating the lens and the iris, the apparatusincluding: a communication part capable of communicating data withrespect to the lens unit; a mounting detector that monitorsattachment/detachment of the lens unit, and outputs first detectioninformation when the lens unit is mounted; a controller capable ofacquiring the setting information from the lens unit via thecommunication part and outputting second detection information whenacquiring the setting information; a first storage that stores eitherthe first detection information outputted from the mounting detector orthe second detection information outputted from the controller; and asecond storage capable of storing the setting information acquired inthe controller, wherein the controller checks detection informationstored in the first storage at a time of start-up of the cameraapparatus, when the first detection information is stored in the firststorage, controls so that the setting information is acquired from thelens unit, and when the second detection information is stored in thefirst storage, controls so that the setting information is acquired fromthe second storage.

According to the above configuration, the transmission operation ofsetting information from the lens unit to the camera unit at a time ofstart-up of the lens unit can be omitted in accordance with the state ofthe lens unit or the camera unit. Therefore, the lens unit can bestarted up at a high speed. Thus, in the camera unit, a shift time fromswitch-on to a photographable state can be shortened to enhance ease ofoperation.

Furthermore, when the lens unit is mounted on the camera unit, thecamera unit does not need to read identification information on the lensunit and can determine the configuration of a lens only based on theinformation of the mounting detector without performing communication.Therefore, the camera system can speed up the start-up of a lensgreatly.

The setting information corresponds to lens data (characteristics data).The communication part corresponds to the first communication terminal413 a, the second communication terminal 413 b, and means for drivingthem. The mounting detector corresponds to the mounting detector 433.The first storage corresponds to the memory in the sub-microcomputer434. The second storage corresponds to the memory 432. The controllercorresponds to the camera microcomputer 431.

[Note 3]

A third camera apparatus of the present invention is a camera apparatusto which a lens unit, with a memory storing setting information requiredfor operating a lens and an iris mounted thereon, isattachable/detachable, and which includes a power cut-off function ofcutting-off at least a power supply to the lens unit when anon-operation period continues for a predetermined period of time, theapparatus including: a communication part capable of communicating datawith respect to the lens unit; a mounting detector that monitorsattachment/detachment of the lens unit, and outputs first detectioninformation when the lens unit is mounted; a controller capable ofacquiring the setting information from the lens unit via thecommunication part and outputting second detection information whenacquiring the setting information; a first storage that stores eitherthe first detection information outputted from the mounting detector orthe second detection information outputted from the controller; and asecond storage capable of storing the setting information acquired inthe controller, wherein the controller checks detection informationstored in the first storage when the power cut-off function is stoppedto start a power supply to the lens unit, when the first detectioninformation is stored in the first storage, controls so that the settinginformation is obtained from the lens unit, and when the seconddetection information is stored in the first storage, controls so thatthe setting information is acquired from the second storage.

According to the above configuration, the start-up time from the statewhere the supply of power to the lens is stopped for power saving (aso-called sleep state of the camera unit and a power-off state of thelens unit) to a photographable state can be shortened. Therefore, thereis a great effect that photographing can be performed without letting aphoto opportunity slip away.

Furthermore, when the lens unit is mounted on the camera unit, thecamera unit does not need to read identification information on the lensunit and can determine the configuration of a lens based only on theinformation of the mounting detector without performing communication.Therefore, the camera system can speed up the start-up of a lensgreatly.

The setting information corresponds to lens data (characteristics data).The communication part corresponds to the first communication terminal413 a, the second communication terminal 413 b, and means for drivingthem. The mounting detector corresponds to the mounting detector 433.The first storage corresponds to the memory in the sub-microcomputer434. The second storage corresponds to the memory 432. The controllercorresponds to the camera microcomputer 431.

[Note 4]

In the second and third camera apparatuses of the present invention, themounting detector is capable of detecting that the lens unit is mountedwhen a power source of the camera apparatus is in an ON or OFF state,and the first storage stores either the first detection information orthe second detection information at all times.

According to the above configuration, even when the camera apparatus isin an OFF state, the mounting of the lens unit can be detected.Therefore, it is not necessary to detect the mounting when the cameraapparatus is switched on, whereby the start-up of the camera system canbe shortened. Thus, photographing can be performed without letting aphoto opportunity slip away.

[Note 5]

A camera apparatus of the present invention is a camera apparatus towhich a lens unit is attachable/detachable, the lens unit having amemory mounted thereon, the memory storing setting information requiredfor operating a lens and an iris and identification information foridentifying each lens unit, the apparatus including: a communicationpart capable of communicating data with respect to the lens unit; acontroller capable of acquiring the identification information and thesetting information from the lens unit via the communication part; and asecond storage that previously stores identification informationcorresponding to various kinds of lens units and setting informationcorresponding to the identification information, wherein, at a time ofstart-up of the camera apparatus, the controller acquires theidentification information from the lens unit, and checks whether or notidentification information matched with the acquired identificationinformation is stored in the second storage, when the identificationinformation is stored in the second storage, controls so that settinginformation corresponding to the identification information is read fromthe second storage, and when the identification information is notstored in the second storage, controls so that the setting informationis acquired from the lens unit.

According to the above configuration, when the camera system is switchedon, only the identification information is acquired from the lens unit,and when the identification information matched with the acquiredidentification information is present in the second storage, theoperation is controlled based on the setting information written in thesecond storage. This makes it unnecessary to perform the processing ofacquiring setting information from the lens unit and the processing ofwriting the acquired setting information in the second storage, so thatthe start-up of the camera system can be sped up.

Furthermore, only the identification information that is a part ofunique information is acquired from the lens unit Therefore, thecommunication between the lens unit and the camera unit is completed ina short period of time, whereby the start-up of the camera system can besped up.

The setting information corresponds to lens data (characteristics data).The communication part corresponds to the first communication terminal413 a, the second communication terminal 413 b, and means for drivingthem. The mounting detector corresponds to the mounting detector 433.The first storage corresponds to the memory in the sub-microcomputer434. The second storage corresponds to the memory 432. The controllercorresponds to the camera microcomputer 431.

[Note 6]

A fifth camera apparatus of the present invention is a camera apparatusto which a lens unit, with a memory storing setting information requiredfor operating a lens and an iris and identification information foridentifying each lens unit mounted thereon, is attachable/detachable,the apparatus including: a communication part capable of communicatingdata with respect to the lens unit; a mounting detector that monitorsattachment/detachment of the lens unit, and outputs first detectioninformation when the lens unit is mounted; a controller capable ofacquiring the identification information and the setting informationfrom the lens unit via the communication part and outputting seconddetection information when acquiring the identification information andthe setting information; a first storage that stores either the firstdetection information outputted from the mounting detector or the seconddetection information outputted from the controller; and a secondstorage which previously stores identification information correspondingto various kinds of lens units and setting information corresponding tothe identification information, and which is capable of storing thesetting information acquired from the lens unit, wherein, at a time ofstart-up of the camera apparatus, the controller acquires theidentification information from the lens unit, and checks whether or notidentification information matched with the acquired identificationinformation is stored in the second storage, when the identificationinformation is stored in the second storage, reads setting informationcorresponding to the identification information from the second storage,and when the identification information is not stored in the secondstorage, checks detection information stored in the first storage, whenthe first detection information is stored in the first storage, acquiressetting information from the lens unit, and when the second detectioninformation is stored, acquires setting information from the secondstorage.

According to the above configuration, it is not necessary to perform theprocessing of acquiring setting information from the lens unit and theprocessing of writing the acquired setting information in the secondstorage, so that the start-up of the camera system can be sped up.

Furthermore, only the identification information that is a part ofunique information is acquired from the lens unit Therefore, thecommunication between the lens unit and the camera unit is completed ina short period of time, whereby the start-up of the camera system can besped up.

The setting information corresponds to lens data (characteristics data).The communication part corresponds to the first communication terminal413 a, the second communication terminal 413 b, and means for drivingthem. The mounting detector corresponds to the mounting detector 433.The first storage corresponds to the memory in the sub-microcomputer434. The second storage corresponds to the memory 432. The controllercorresponds to the camera microcomputer 431.

[Note 7]

In a fourth camera apparatus of the present invention, the secondstorage may be composed of a read-only memory. According to thisconfiguration, the cost can be reduced.

[Note 8]

In second to fifth camera apparatuses, the controller may be capable ofcontrolling any one of autofocusing, autoexposure, and shakingcorrection in the lens unit.

According to the above configuration, when any one of autofocusing,autoexposure, and shaking correction is controlled, lens state data isacquired from the lens unit, and various kinds of controls can beperformed based on the acquired lens state data and the previouslyacquired setting information. Thus, the amount of data to becommunicated at a time of various kinds of controls is small, so thatvarious kinds of controls can be performed with a high response.

[Note 9]

A camera system of the present invention includes the camera apparatusaccording to any one of the first to fifth camera apparatuses, and alens unit being attachable/detachable to the camera apparatus andcapable of communicating data with respect to the camera apparatus.

According to the above configuration, the transmission operation ofunique information from the lens unit to the camera unit at a time ofstart-up of the lens unit can be omitted in accordance with the state ofthe lens unit or the camera unit. Therefore, the lens unit can bestarted up at a high speed. Thus, in the camera unit, a shift time fromswitch-on to a photographable state can be shortened to enhance ease ofoperation.

Furthermore, when the lens unit is mounted on the camera unit, thecamera unit does not need to read identification information on the lensunit and can determine the configuration of a lens only based on theinformation of the mounting detector without performing communication.Therefore, the camera system can speed up the start-up of a lensgreatly.

The present invention is useful for a camera system to which a lens unitand a camera unit are attachable/detachable, and in which informationcan be communicated between the lens unit and the camera unit.

The invention may be embodied in other forms without departing from thespirit or essential characteristics thereof. The embodiments disclosedin this application are to be considered in all respects as illustrativeand not limiting. The scope of the invention is indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning and range of equivalency of theclaims are intended to be embraced therein.

1.-17. (canceled)
 18. A camera apparatus to which a lens unit containingat least a lens and an iris is attachable/detachable, capable ofacquiring unique information set in the lens unit, comprising: acommunication part to which the unique information is inputted from thelens unit; a second storage capable of storing the unique informationinputted to the communication part; and a controller that controls thelens unit so that the unique information is outputted, wherein theunique information at least composed of identification information foridentifying the lens unit and characteristic information, correspondingto the identification information, for controlling various operations ofthe lens and the iris in the lens unit, the controller controls so thatthe unique information is acquired from the lens unit when an operationof attaching/detaching the lens unit is performed.
 19. The cameraapparatus according to claim 18, wherein the apparatus furthercomprises: a mounting detector that monitors attachment/detachment ofthe lens unit, and outputs first detection information when the lensunit is mounted; and a first storage that stores the first detectioninformation outputted from the mounting detector, wherein when the firstdetection information is outputted from the mounting detector, thecontroller acquires the identification information from the lens unit,and checks whether or not identification information matched with theacquired identification information is stored in the second storage, ina case where the identification information is stored in the secondstorage, the controller controls so that characteristic informationcorresponding to the identification information is read from the secondstorage, while in a case where the identification information is notstored in the second storage, the controller acquires the characteristicinformation corresponding to the identification information from thelens unit, and stores to the second storage the characteristicinformation and the identification information acquired from the lensunit.
 20. The camera apparatus according to claim 18, wherein theapparatus includes a power cut-off function of cutting off at least apower supply to the lens unit when a non-operation period continues fora predetermined period of time, when the power cut-off function isstopped to start a power supply to the lens unit, the controlleracquires the identification information from the lens unit, and checkswhether or not identification information matched with the acquiredidentification information is stored in the second storage, in a casewhere the identification information is stored in the second storage,the controller controls so that characteristic information correspondingto the identification information is read from the second storage, whilein a case where the identification information is not stored in thesecond storage, the controller acquires the characteristic informationcorresponding to the identification information from the lens unit, andstores to the second storage the characteristic information and theidentification information acquired from the lens unit.
 21. The cameraapparatus according to claim 18, wherein the second storage is composedof a read-only memory.
 22. The camera apparatus according to claim 18,wherein the controller is capable of controlling any one ofautofocusing, autoexposure, and shaking correction in the lens unit. 23.A camera system comprising: a camera apparatus; and a lens unit beingattachable/detachable to the camera apparatus and capable ofcommunicating data with respect to the camera apparatus, wherein thecamera apparatus capable of acquiring unique information set in the lensunit, comprising: a communication part to which the unique informationis inputted from the lens unit; a second storage capable of storing theunique information inputted to the communication part; and a controllerthat controls the lens unit so that the unique information is outputted,wherein the unique information at least composed of identificationinformation for identifying the lens unit and characteristicinformation, corresponding to the identification information, forcontrolling various operations of a lens and an iris in the lens unit,the controller controls so that the unique information is acquired fromthe lens unit when an operation of attaching/detaching the lens unit isperformed.